What about when we are dealing with institutions though? - I suspect that a great deal depends on our motivations - if arising out of anger or hatred then we have no entitlement.
However, if we feel that we have been cheated by an insurance company or a power giant or similar where clearly the personal element is entirely lacking, I suspect that the same thinking does not apply.
If I have been victimised by a large body, I shall tell everybody I know and shall do my utmost to avoid the wrongdoer in the future.
If however this results in cutting-off-the-nose-to-spite-the-face syndrome - we should act with wisdom.
Being a believer certainly makes you consider hard the motivations behind your actions!